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Discussion Starter #1 (Edited)
Hey guys,

planning my winter modding session on the TBS and think I'm getting close to a plan. I've combed through quite a few of the posts but, although I have a finished product in mine, I haven't been able to come up with a definitive list of "other parts" needed such as gaskets and the like. This is particularly pertinent to the cam swap as well as any mag wheel swap tips.



As for the plan, it involved an USD front end, mag wheels, green can swap, and some necessary maintenance. Below is my admittedly crappy photoshop rendering of what I'm planning:







Suspension & Wheels:

Front:

k6 GSXR 600 forks. Specs: 738mm stock length + 15mm extenders = 752mm overall length (29.6"). 310mm rotor size. All balls racing fork swap bearings ordered. I lucked out finding a set of used forks that have GP suspension internals & extenders and that were set up for a 175lb (in gear) rider, which is just about my weight.



05+ zx6r front wheel with zx14 310mm rotors. I am unsure of the width of the hub so hopefully will work with the gsxr forks. Gsxr wheels are out as I hate 3 spoke wheels with a passion and would prefer not to relive the 90s.



Rear:



zx6r shock (no real need for it but I have one sitting around and it's more compact than the TBS remote reservoir shock).



05+ zx6r rear wheel with zx11 250mm rotor and 530 sprocket. Trophy rear brake assembly (caliper, bracket, torque arm). The rotor diameter is 5mm less than the Trophy, but that's less than 1/10 an inch of reduced pad contact, so I'm not too worried.



I don't know for sure that any of the above will work, but I think it's worth a shot and hey, that's half the fun of custom stuff. I really want to switch to mags as this is my daily rider here in NYC and sits out on the street all riding season. Mags are lighter, easier to maintain, fit standard size sportbike tires, and infinitely easier to clean. If I can't get the zx6r wheels to fit, I'll throw em back on ebay and pick up an 08+ Harley narrow glide dual disc hub and hayabusa rotors or the cognito moto front hub and stick with spokes.



Engine:

Green cams & rejet

igniter off 98hp Triple or programmable unit

check/adjust valves

change fluids & flush cooling system



for this, I assume I need a head gasket as well as 25mm shims. I'm going to get a Haynes manual prior to going down this road, but could certainly use some real world pointers as well as a parts shopping list for gaskets, shims, etc.





Body:

White paint



Cheers,

Jason
 

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Looks like a plan stan! :)

The cam swap won't mean any shim changes, by itself. They'll only be needed if clearances are already out of spec. (All the base diameters remain the same, and Triumph's maching is done to far higher tolerances.)

It's not worth buying any new shims until you know what you need. You'll probably find some will swap into other positions, so out of say 5 that need adjustment, only two new shims will be needed.

If you're going to use the GSXR yokes with a much smaller offset than stock, unless you tilt the bike forward to steepen the effective steering head angle, the steering response will be markedly slower.

In rough terms, you'll need to tilt the ride heights about a *total* of 70 to 80mm. By total, I mean the sum of increased ride height at the back and decreased ride height at the front. For easy trigonometry calculation, you may assume the total tilt to represent the short vertical side of a very long and skinny right angle triangle, where the wheelbase is the 'adjacent' side to the small angle. Strictly speaking, the wheelbase will also shorten by a couple of inches (a good thing for agility), but this doesn't change the accuracy of calc much. (You might want to alter the photoshop job to get an idea what it will look like.)

In other words, to keep a reasonably agile front trail figure, the GSXR yokes (or any modern sport bike - they all use similar geometry) will also need the much steeper steering head angle these bikes use as well.
 

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Discussion Starter #5
I meant valve cover gasket, just mistyped. ?

IrlMike, thankfully this isn't my first usd fork conversion and plan to raise the rear a bit to compensate. Also given the slight decrease in rear tire diameter, I'm lucky to have a good amount of fork real estate to experiment with moving them up or down in the triples. However, it being a decade since I last owned a sportbike, I've found the TBS front wheel to be a little twitchy and am actually looking to reduce that a bit.

Zee, I'll certainly take you up on the offer for the Haynes.

Lower gsxr triple and zx6r front axle arrived yesterday and the forks are arriving today. As winter is approaching and my garage space fell through, I've also had to order a 6x8 temporary garage for the backyard to do all this work and store both bikes. Should be a fun winter
 

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Ouch, that's a small space to be doing all this.. but great stuff - looking forward to your pictorial updates! ;)
 

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Great looking project. Definitely keep us updated. I would like to do an USD fork conversion in the future myself.
 

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Which exhaust do you have in your photoshop picture? Looks like 3to1, that already installed?

Jason - I totally missed the 3-1 exhaust. If you are planning that too, then count me in for sure. I'm dying to do that too
 

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Discussion Starter #11
Jason - I totally missed the 3-1 exhaust. If you are planning that too, then count me in for sure. I'm dying to do that too

Nope, I was just lazy and used a modified bike as the basis for my photoshop
 

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I have done a swap with a 955i sprint front end and rear rim on a tbs nice easy direct swap on the rear.
great way to get mag wheels on with no modification front end bolted right up.
 

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Discussion Starter #13
I have done a swap with a 955i sprint front end and rear rim on a tbs nice easy direct swap on the rear.

great way to get mag wheels on with no modification front end bolted right up.

Easier way to get mag wheels but I'm still looking to upgrade to usd forks and multi spoke my wheels (as stated above, I'm not a fan of three spoke mags). I figure the winter will be more than enough time to figure out the usd forks, mag wheel swap, spacers, adapters, etc.
 

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Discussion Starter #14
Got the work shed up and parts are starting to arrive

Not the most spacious, but the biggest I could easily fit in my NYC backyard. With both bikes being about 7' long, the 6x8 shed is going to be tight but hopefully workable.


Forks arrived and are in good shape. Stock anodizing is in pretty good shape with only light scratches and the fork stanchions have been titanium nitride coated.


Also received the lower triple and all balls conversion bearings (not pictured) and have ordered the Trophy rear caliper setup. For the front, I found a set of GSXR front calipers at a ridiculously cheap price so scrapped the idea for the R6 monoblock conversion.

Heading out of the country on vacation for almost 2 weeks, so the bikes go into the shed tonight.
 

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Discussion Starter #15 (Edited)
Finally had a little time and energy to start wrenching. Was in Mexico and Costa Rica for 11 days and picked up a mosquito borne illness in CR that put me on my ass for the past week. However, finally feeling better and got home from work early enough to run over to my neighborhood shop and have the rear tire mounted then rolled the bike out of the shed and started mocking up the rear wheel then started tearing down the front end.



As usual, my little shop dog was out there nosing around the bike.







Got the rear wheel off and weighed them.



Stock rear wheel with tire/sprocket/rotor = 50.0lbs

zx6r rear wheel with tire/rotor (no sprocket yet) = 30.9lbs



I'm hoping to do a 520 conversion with an aluminum or steel/aluminum rear sprocket to keep the unsprung weight down.



Good shot of the old brake bracket





250mm zx9 rotor for use with the lower Triumph Trophy caliper and bracket





Trophy rear caliper and bracket mocked up







Wheel in - waiting on getting the sprocket and chain installed before taking final measurements for spacers.




fat ass (the seat is going to be trimmed down. It's the result of paying way too much money to the "best" motorcycle upholsterer in NYC who has now become a bit big for her britches)





Started disassembly on the front end as well, but stalled out when I couldn't get the top yoke off. Tried heat and a dead blow hammer but it wouldn't budge. Going to rent a puller and see if that will do the trick. If not, I'm at a loss. Any ideas?



 

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Discussion Starter #16
getting there... A 3 jaw puller worked a treat getting the top triple off.


getting the lower yoke off, I noticed a mismatched set of bearings. Bottom is a tapered roller bearing and the top is a sealed bearing. I'm used to Triumphs (and other bikes) having caged ball bearings top and bottom, which I've usually switched for tapered roller bearings. Anyone ever seen a setup like this or am I looking at some creative liberties taken by a previous owner?


Started mocking up the gsxr front end

with the extensions, the front forks are 29.5" to the centerline of the axle

got the bars on to figure out the approximate location for the new steering stops

The stock stops will be shaved and the yoke drilled and tapped for bolts to act as steering stops. The entire lower yoke will be smoothed and powder coated black

glad I went with the black forks. Blend in much better than gold or silver folks
 

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Bearings are correct. Be sure you don't tighten it to the point where the circlip pops out of the top bearing. Don't a$k me how I know thi$.

Earlier bikes had some sort of insert in the top of the headstock and used a second tapered bearing. I don't think they are interchangeable, though. I think the later headstock has a sleeve pressed in to reduce the diameter slightly to fit the roller bearing.
 

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Looking great! :)

Yep, those bearings are the stock set up. The top bearing doesn't see a fraction of the load of the lower set, radially and axially. So, if it suits, and I've even read that it has some advantage, you can fit a ball type at the top. In my conversion I used a double row angular ball type as it allowed a narrower race width to suit the new (larger) stem diameter, and its load ratings pretty much matched the original. The top bearing can be recessed in the headstock down to a bottom ridge about 19mm down, but the inner surface needed some cleaning up (mostly paint) on mine. I prefer to buy branded bearings not the cheap ebay stuff.

Have you measured the yoke offsets of the old and new yokes and done any trail calculation comparisons?
 

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Discussion Starter #19
Looking great! :)

Yep, those bearings are the stock set up. The top bearing doesn't see a fraction of the load of the lower set, radially and axially. So, if it suits, and I've even read that it has some advantage, you can fit a ball type at the top. In my conversion I used a double row angular ball type as it allowed a narrower race width to suit the new (larger) stem diameter, and its load ratings pretty much matched the original. The top bearing can be recessed in the headstock down to a bottom ridge about 19mm down, but the inner surface needed some cleaning up (mostly paint) on mine. I prefer to buy branded bearings not the cheap ebay stuff.

Have you measured the yoke offsets of the old and new yokes and done any trail calculation comparisons?
when I was thinking about the project, I did the calculations. With the forks flush with the top clamp, the trail is 4.69 (vs. stock 4.13) but of course the rear suspension and tire diameters will affect things.
 

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Discussion Starter #20
Came home after helping a fellow RAT with his own USD fork conversion to find the front wheel had arrived. Quickly mounted it up to see clearances and rotor fitment and it seems like it'll work just fine.

everything lines up nicely[


Wheels right now are mismatched colors but both will be gloss black eventually. Still working out what color I'm going to powdercoat the calipers.
 
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